Respiratory hygiene practices by the public during the 2009 influenza pandemic: an observational study

To describe the public use of respiratory hygiene behaviours during the 2009 influenza pandemic and to test the feasibility of an observational method.

Respiratory behaviour was systematically observed at three public settings during August 2009 in the capital city of New Zealand (Wellington). Data on each coughing or sneezing event were collected.

A total of 384 respiratory events were observed, at a rate of 0·8 cough/sneeze per observed-person-hour. Around a quarter of respiratory events (27·3%) were uncovered, and there was infrequent use of the responses recommended by health authorities (i.e., covering with a tissue or handkerchief at 3·4% and covering with elbow or arm at 1·3%). Respiratory event rates were higher in all settings that were 'high flow' (for people movement) compared to 'low flow' settings. Uncovered events were more common among people at the hospital entrance versus the hospital café [risk ratio (RR) = 7·8, 95% confidence interval (CI): 1·1-52·6] and when a person was located within 1 m of others (RR = 1·5, 95% CI: 1·1-1·9). Observing respiratory hygiene was found to be feasible in all of the selected public locations. There was good agreement between observing pairs about whether or not respiratory events occurred (inter-observer correlation = 0·81) and for uncovered versus covered events (total Cohen's kappa score = 0·70).

It was feasible to document respiratory hygiene behaviour in public urban settings during a influenza pandemic. Respiratory hygiene advice was not being adequately followed by this population towards the end of the first wave of the pandemic.